Institute for Physics
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Item type:Publication, Comparative analysis of different nuclear medicine techniques in evaluation of renal function(VIA MEDICA Journals, 2023)Aleksandra Peshevska, Tanja Makazlieva, Venjamin Majstorov, Lambe Barandovski, Irena Rambabova-Bushljetik, Daniela MiladinovaIntroduction: Nuclear medicine (NM) methods play an important role in the evaluation of renal function in a wide range of clinical indications. The aim of our study was to evaluate the correlation between measured GFR (mGFR) obtained by the three-plasma sample slope-intercept NM method (TPSM) — reference method vs. estimated GFR (eGFR) using Fleming’s single plasma sample method (SPSM) at 120 min, 180 min, and 240 min and correlation of reference method with eGFR with camera-based Gates’ protocol. Material and methods: A total of 82 subjects (33 male/49 female) with a mean age of 54.87 ± 15.65 years were included and mGFR value was obtained by the three-plasma sample slope-intercept NM method and eGFR was obtained with Fleming’s single sample method. eGFR was also quantified with the camera-based Gates’ protocol after i.v. application of [99mTc]Tc-DTPA. Results: Our study revealed a very strong positive significant correlation between all three SPSMs with the TPSM as the reference method. Between the Gates’ method and the TPSM in the group of patients with mGFR ≥ 61–84 mL/min/1.73 m2 and mGFR ≥ 84 mL/min/1.73 m2, a moderate positive statistically significant correlation was obtained. Conclusions: The SPSM method shows a very strong correlation with the reference and low bias in all three groups of patients and can be routinely used for GFR estimation. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Spatial distribution and isotopic signatures of N and C in mosses across Europe(Elsevier, 2025-01-01)Sheila Izquieta-Rojano, Yasser Morera-Gómez, David Elustondo, Esther Lasheras, Carolina Santamaría, Julen Torrens-Baile, Renate Alber, Lambe Barandovski, Mahmut Coşkun, Munevver Coskun, Helena Danielsson, Ludwig De Temmerman, Harry Harmens, Zvonka Jeran, Sébastien Leblond, Javier Martínez-Abaigar, Encarnación Núñez-Olivera, Roland Pesch, Juha Piispanen, Gerhard Soja, Zdravko Spiric, Trajče Stafilov, Lotti Thöni, Jesús Miguel SantamaríaThe accumulation of nitrogen (N) in moss tissue has proven to be a reliable marker of increasing N deposition. However, this measurement does not offer additional data about the origin of pollution. In this respect, the analysis of the N isotopic ratios might be a helpful tool in providing supplementary information about the nature of the nitrogenous species in biomonitoring surveys. Furthermore, isotopic signatures have been extensively used in the study of N and carbon (C) biogeochemical cycles. The main purpose of this study was to determine N and C elemental contents and their stable isotopes in mosses to investigate atmospheric pollution patterns across Europe. We aimed at identifying the main N polluted areas and evaluating the potential use of isotopic signatures in the attribution of pollution sources at a regional scale. With these objectives in mind, >1300 samples from 15 countries from Europe, all of them participants of the ICP-Vegetation programme 2005–2006, were analyzed for their C and N contents and δ15N and δ13C. The results were compared to those derived from EMEP model, which provided modeled deposition and emission data, as well as to the predominant land uses at the sampling sites (based on CORINE Land Cover). This evaluation suggests that additional measurements of stable C and N isotopes in mosses could be a valuable tool in European environmental surveys. Such measurements not only provide useful information for identifying probable pollution sources but also enable the quantification of their contributions, serving as biological indicators of significant environmental processes. This study presents the first quantitative assessment of major atmospheric nitrogen (N) sources based on stable isotope analysis on a European scale, establishing a framework for evaluating historical changes in N across the region. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Mercury Pollution in Terrestrial Ecosystems of North Macedonia: Insights from an 18-Year Moss Biomonitoring Programme(MDPI, 2025-12-22)Katerina Bačeva Andonovska, Robert Šajn, Jasminka Alijagić, Trajče Stafilov, Lambe BarandovskiMoss biomonitoring was conducted in 2002, 2005, 2010, 2015 and 2020 to evaluate atmospheric mercury (Hg) deposition across N. Macedonia as part of a comprehensive survey of potentially toxic elements (PTEs). More than 70 samples of the dominant moss species Hypnum cupressiforme and Homalothecium lutescens were collected during the summer field campaigns. Mercury concentrations were determined using cold vapour atomic absorption spectrometry and inductively coupled plasma mass spectrometry (ICP-MS). The results revealed marked temporal fluctuations: median Hg content increased from 56 µg/kg in 2002 to 68 µg/kg in 2005, peaked at 93 µg/kg in 2010, then decreased to 84 µg/kg in 2015, and further to 52 µg/kg in 2020. Over the study period, Hg concentrations ranged from 10 to 595 µg/kg, with the highest variability observed in 2010. Spatial distribution maps and regional comparisons indicate that elevated Hg contents correspond predominantly to anthropogenic sources, particularly in industrialised zones and regions affected by mining and metallurgical activities. The 2020 dataset shows a significantly lower median value (52 µg/kg) compared to previous surveys, indicating a slight improvement in air quality, although local hotspots persist. These results highlight the importance of long-term moss biomonitoring as a cost-effective approach for tracking atmospheric mercury trends and informing national environmental policy. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Докторска дисертација: ОПРЕДЕЛУВАЊЕ ДИЈАГНОСТИЧКИ РЕФЕРЕНТНИ ВРЕДНОСТИ КАЈ МАМОГРАФСКИТЕ СНИМАЊА(PMF-UKIM, 2025-12-04)Mirjeta Mediji Arifi (Мирјета Медији Арифи)Diagnostic reference levels (DRLs) in digital mammography were determined from 31 040 digital mammography images acquired from diagnostic and screening examination data from eight state-managed mammography centers/units in the Republic of North Macedonia (RM). The main objective is to establish a diagnostic reference level for mammography examinations at different ranges of breast thickness. Approximately 30 000 mammography images were used to evaluate mean glandular dose (MGD) and compressed breast thickness (CBT) for each projection, craniocaudal (CC) and mediolateral oblique (MLO). The stratified DRL was derived by calculating the 75th percentile of the MGD across all the samples at various CBT ranges for both projections. The overall median MGDs, minimum, and maximum were calculated to be 1.15 mGy, 0.1 mGy, and 9.93 mGy, respectively. As the CBT increased from 7 to 120 mm, the 75th percentile of the MGD increased from 0.94 mGy to 3.67 mGy for CC, and from 0.44 mGy to 4.91 mGy for MLO projections. The study established local DRLs for the digital mammography systems at the 75th percentile, which compared well with the values reported for other countries/regions. The DRL defined per CC and MLO image view for a specific CBT indicated that at least one mammography facility needs optimization. In mammography, radiation dose is typically expressed as the Mean Glandular Dose (MGD), which represents the dose delivered to the glandular tissue of the breast. This study compares MGD estimates obtained using three different methodologies: (I) MGD-Dance-LIBRA – Calculated manually for each patient using Dance’s formula, incorporating Mammographic Breast Density (MBD) values derived from the LIBRA application (Laboratory for Individualised Breast Radiodensity Assessment), thereby replacing Dance’s standard glandularity assumption with image-specific values; (II) MGD-Dance – Calculated using Dance’s formula with the conventional assumption of 50% glandularity; (III) MGD-Displayed – Extracted directly from the DICOM header of each mammogram. A total of 688 anonymized mammograms from 172 women undergoing routine screening were analyzed, with complete technical and patient-related data. The mean MGD values obtained by the three methods were: MGD-Dance-LIBRA: 2.97 mGy; MGD-Dance: 2.78 mGy; MGD-Displayed: 2.81 mGy. The average glandularity across the dataset was estimated at 14%. A strong correlation was observed between MGD-Dance and MGD-Dance-LIBRA values (R² = 0.9865). The refined dose estimation using image-specific glandularity from LIBRA consistently produced slightly higher values compared to the standard Dance method, highlighting the impact of the commonly assumed 50% glandularity, which overestimates the true average density. Incorporating individualized breast density estimates from the LIBRA application into Dance’s formula provides a more refined and accurate method for calculating Mean Glandular Dose in digital mammography In a systematic review, we examine the establishment of Diagnostic Reference Levels (DRLs) in digital mammography across 18 European countries, based on studies from 2005 to 2025. A total of 353 articles were identified through the comprehensive search of academic networks: Google Scholar, PubMed, Research Gate, and Academia. Only 18 peer-reviewed studies met the inclusion criteria reporting Mean Glandular Dose (MGD)-based DRLs from Finland to Malta. Eight studies used patient data, four used phantom measurements, and six used both. To overcome the challenging comparison of the variety of reported parameters, we undertook some data harmonisation procedures, focusing on a common Compressed Breast Thickness (CBT) range of 50–59 mm. The DRLs varied notably by country, with 75th percentile MGDs ranging from 1.1 to 2.6 mGy and 95th percentile from 1.6 to 2.9 mGy, averaging to 1.44 mGy, which is lower than the achievable European level (2 mGy). The harmonisation approach enabled the derivation of a comparable dataset of average MGDs, facilitating cross-country comparisons and insights into radiation dose optimisation in digital mammography across Europe. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Trends in Atmospheric Nitrogen Deposition in Macedonia Studied by Using the Moss Biomonitoring Technique(MDPI, 2024-10-28)Katerina Bačeva Andonovska, Trajče Stafilov, Robert Šajn, Biljana Jordanoska Shishkoska, Valentina Pelivanoska, Lambe BarandovskiThis study examined the nitrogen content in moss samples collected across Macedonia over a 15-year period (2005, 2010, 2015 and 2020) from 72 consistent sampling locations. The nitrogen content was determined using the Kjeldahl method, providing insight into the trends of atmospheric nitrogen deposition across different regions. Descriptive statistical analyses, including spatial distribution maps, were used to compare the temporal variations and regional nitrogen levels. In addition, box-plots (P25–P75) and whiskers (P5–P95) were constructed to provide a comprehensive view of the variability across different tectonic units and zones, allowing for an in-depth understanding of the spatial distribution of nitrogen across the country. The study revealed that the median nitrogen content in moss samples decreased from 1.21% in 2005 to 1.04% in 2015, followed by a slight increase to 1.07% in 2020. The highest nitrogen concentrations were consistently found in areas with heavy agricultural activities and high traffic volumes, indicating the direct impact of these anthropogenic factors. The comparisons across regions and geological zones also highlighted the substantial variation in nitrogen levels, reflecting the diverse environmental pressures in different parts of Macedonia. This long-term analysis not only offers valuable insights into the trends in nitrogen pollution but also underlines the necessity for targeted policy interventions, particularly in the regions where nitrogen levels remain persistently high. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Trends in Atmospheric Nitrogen Deposition in Macedonia Studied by Using the Moss Biomonitoring Technique(MDPI, 2024-10-28)Katerina Bačeva Andonovska, Trajče Stafilov, Robert Šajn, Biljana Jordanoska Shishkoska, Valentina Pelivanoska, Lambe BarandovskiThis study examined the nitrogen content in moss samples collected across Macedonia over a 15-year period (2005, 2010, 2015 and 2020) from 72 consistent sampling locations. The nitrogen content was determined using the Kjeldahl method, providing insight into the trends of atmospheric nitrogen deposition across different regions. Descriptive statistical analyses, including spatial distribution maps, were used to compare the temporal variations and regional nitrogen levels. In addition, box-plots (P25–P75) and whiskers (P5–P95) were constructed to provide a comprehensive view of the variability across different tectonic units and zones, allowing for an in-depth understanding of the spatial distribution of nitrogen across the country. The study revealed that the median nitrogen content in moss samples decreased from 1.21% in 2005 to 1.04% in 2015, followed by a slight increase to 1.07% in 2020. The highest nitrogen concentrations were consistently found in areas with heavy agricultural activities and high traffic volumes, indicating the direct impact of these anthropogenic factors. The comparisons across regions and geological zones also highlighted the substantial variation in nitrogen levels, reflecting the diverse environmental pressures in different parts of Macedonia. This long-term analysis not only offers valuable insights into the trends in nitrogen pollution but also underlines the necessity for targeted policy interventions, particularly in the regions where nitrogen levels remain persistently high. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, In Vitro and in Silico Insights on the Biological Activities, Phenolic Compounds Composition of Hypericum perforatum L. Hairy Root Cultures(Computers, Materials and Continua (Tech Science Press), 2023); ; Gadzovska Simic, Sonja - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Atmospheric Heavy Metal Deposition in North Macedonia from 2002 to 2010 Studied by Moss Biomonitoring Technique(MDPI, 2020-08-30)Lambe Barandovski, Trajče Stafilov, Robert Šajn, Marina Frontasyeva, Katerina Bačeva AndonovskaMoss biomonitoring technique was used for a heavy-metal pollution study in Macedonia in the framework of the International Cooperative Program on Effects of Air Pollution on Natural Vegetation and Crops (UNECE IPC Vegetation). Moss samples (n = 72) were collected during the summers of 2002, 2005, and 2010. The contents of 41 elements were determined by neutron activation analysis, atomic absorption spectrometry, and inductively coupled plasma atomic emission spectrometry. Using factor and cluster analyses, three geogenic factors were determined (Factor 1, including Al, As, Co, Cs, Fe, Hf, Na, Rb, Sc, Ta, Th, Ti, U, V, Zr, and rare-earth elements–RE; Factor 4 with Ba, K, and Sr; and Factor 5 with Br and I), one anthropogenic factor (Factor 2, including Cd, Pb, Sb, and Zn), and one geogenic-anthropogenic factor (Factor 3, including Cr and Ni). The highest anthropogenic impact of heavy metal to the air pollution in the country was from the ferronickel smelter near Kavadraci (Ni and Cr), the lead and zinc mines in the vicinity of Makedonska Kamenica, Probištip, and Kriva Palanka in the eastern part of the country (Cd, Pb, and Zn), and the former lead and zinc smelter plant in Veles. Beside the anthropogenic influences, the lithology and the composition of the soil also play an important role in the distribution of the elements. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Atmospheric Mercury Deposition in Macedonia from 2002 to 2015(MDPI, 2020-12-21)Trajče Stafilov, Lambe Barandovski, Robert Šajn, Katerina Bačeva AndonovskaThe moss biomonitoring technique was used in 2002, 2005, 2010 and 2015 in a potentially toxic elements study (PTEs) in Macedonia. For that purpose, more than 70 moss samples from two dominant species (Hypnum cupressiforme and Homalothecium lutescens) were collected during the summers of the mentioned years. Total digestion of the samples was done using a microwave digestion system, whilst mercury was analyzed by cold vapour atomic absorption spectrometry (CV–AAS). The content of mercury ranged from 0.018 mg/kg to 0.26 mg/kg in 2002, from 0.010 mg/kg to 0.42 mg/kg in 2005, from 0.010 mg/kg to 0.60 mg/kg in 2010 and from 0.020 mg/kg to 0.25 mg/kg in 2015. Analysis of the median values shows the increase of the content in the period 2002–2010 and a slight reduction of the air pollution with Hg in the period 2010–2015. Mercury distribution maps show that sites with increased concentrations of mercury in moss are likely impacted by anthropogenic pollution. The results were compared to similar studies done during the same years in neighboring countries and in Norway—which is a pristine area and serves as a reference, and it was concluded that mercury air pollution in Macedonia is significant primarily in industrialized regions. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Innovative Learning Activities for Ethnically Diverse Students in Macedonian Science Education(Center for Educational Policy Studies Journal, 2024)Katerina Rusevska, Lambe Barandovski, Vladimir M. Petruševski, Aleksandra Naumoska, Slavica Tofilovska, Marina StojanovskaA game-based approach is widely used to increase students’ motivation through their active participation, whereby research is interwoven with fun and competition is incorporated with cooperation. Working in teams or groups encourages students to exchange their opinions, to try to find solutions together or to win a game. In this way, they learn and improve skills such as collaboration and responsibility. Several activities involving the 5E model as part of inquiry-based science education and an escape room as part of game-based learning were used in science classes (chemistry, biology and physics). The activities were designed on three different topics – gases, ecology and electrical circuits – within the project “Diversity in Science towards Social Inclusion – Non-formal Education in Science for Students’ Diversityâ€. The activities focused on the students’ self-concept towards science, interest in the subject, motivation and career aspirations in STEM, as well as the effectiveness of the implemented activities. The study aimed to assess the potential advantages of implementing activities in an ethnically diverse environment, benefiting both students and teachers. Pre- and post-questionnaires were designed and distributed to 190 students from various primary and secondary schools in Macedonia. The present paper provides an overview of game-based activities as well as a brief analysis of the pre- and post-questionnaire responses from students, focusing on the topic of ecology.